How many moles are in 33.9 g of water?

Answer 1

Avogadro's Number = Avogadro's number = 6.0221415 × 10236.02×1023 (abbreviated); this is the number of atoms, ions, molecules, or anything else in 1 mole. 0.33 moles of water would have 0.33·6.02×1023 = 1.99×1023 molecules. However water's formula is H2O, so it has 3 atoms per molecule.

(0.33 moles) × (6.02×1023 molecules per mole) = 1.99×1023 molecules.

1.99×1023 molecules × 3 atoms per molecule = 5.96×1023 atoms

(0.33 moles) × (6.0221415 × 1023molecules per mole) = 1.987306695×1023 molecules.

1.987306695×1023 molecules × 3 atoms per molecule =5.961920085 1023 atoms

I would use the rounded answer, 5.96×1023 atoms

Answer 2

Number of moles = mass / relative Atomic Mass

The relative atomic mass of water is 16 (for O) + 2 (for the 2 H) = 18

So 33.9 / 18 = 1.88 mols

Answer 3

3.5 moles